Dictionary

lose

—v.t.1. to come to be without (something in one's possession or care), through accident, theft, etc., so that there is little or no prospect of recovery: I'm sure I've merely misplaced my hat, not lost it.2. to fail inadvertently to retain (something) in such a way that it cannot be immediately recovered: I just lost a dime under this sofa.3. to suffer the deprivation of: to lose one's job; to lose one's life.4. to be bereaved of by death: to lose a sister.5. to fail to keep, preserve, or maintain: to lose one's balance; to lose one's figure.6. (of a clock or watch) to run slower by: The watch loses three minutes a day.7. to give up; forfeit the possession of: to lose a fortune at the gaming table.8. to get rid of: to lose one's fear of the dark; to lose weight.9. to bring to destruction or ruin (usually used passively): Ship and crew were lost.10. to condemn to hell; damn.
11. to have slip from sight, hearing, attention, etc.: to lose him in the crowd.12. to stray from or become ignorant of (one's way, directions, etc.): to lose one's bearings.13. to leave far behind in a pursuit, race, etc.; outstrip: She managed to lose the other runners on the final lap of the race.14. to use to no purpose; waste: to lose time in waiting.15. to fail to have, get, catch, etc.; miss: to lose a bargain.16. to fail to win (a prize, stake, etc.): to lose a bet.17. to be defeated in (a game, lawsuit, battle, etc.): He has lost very few cases in his career as a lawyer.18. to cause the loss of: The delay lost the battle for them.19. to let (oneself) go astray, miss the way, etc.: We lost ourselves in the woods.20. to allow (oneself) to become absorbed or engrossed in something and oblivious to all else: I had lost myself in thought.21. (of a physician) to fail to preserve the life of (a patient).
22. (of a woman) to fail to be delivered of (a live baby) because of miscarriage, complications in childbirth, etc.

—v.i.1. to suffer loss: to lose on a contract.2. to suffer defeat or fail to win, as in a contest, race, or game: We played well, but we lost.3. to depreciate in effectiveness or in some other essential quality: a classic that loses in translation.4. (of a clock, watch, etc.) to run slow.
5. lose face. See face (def. 30).
6. lose out, to suffer defeat or loss; fail to obtain something desired: He got through the preliminaries, but lost out in the finals.